This answer is incorrect.
You correctly chose to add the two amounts together. However you must remember that when completing a mixed units problem you must keep track of the units. There are two ways of completing this problem.
Say you have to add 5 feet 7 inches to 2 feet 6 inches.
5 feet 7 inches converts as
5 feet x 12 inches/foot = 60 inches
60 inches + 7 inches = 67 inches
2 feet 6 inches converts as
2 feet x 12 inches/foot = 24 inches
24 inches + 6 inches = 30 inches
then
67 inches + 30 inches = 97 inches
Convert this back to mixed units
97 inches divided by 12 inches/foot = 8 feet 1 inch.
Say you have to add 5 feet 7 inches to 2 feet 6 inches.
Start with the inches.
7 inches + 6 inches = 13 inches
But 13 inches is more than 1 foot.
13 inches divided by 12 inches/foot = 1 foot 1 inch.
Now add the feet
5 feet + 2 feet + 1 foot (from the inches column) = 8 feet
Therefore the answer is 8 feet 1 inch.
If you feel that you understand the above example, let's try another problem.
If George placed a 3 feet 9 inches tall model airplane atop a 1 foot 4 inches tall display base, how tall would the airplane and base be together?
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